back IGCSE Chemistry
| Reaction |
From |
To |
| Alkenes and bromine water |
orange |
colourless |
| Alkanes and bromine water |
orange |
remains orange |
| Chlorine with damp litmus |
blue |
red then white/bleached |
| Hydrogen chloride – dry with blue litmus |
blue |
remains blue |
| Hydrogen chloride with damp blue litmus/hydrogen chloride in water with blue litmus |
blue |
red |
| Hydrogen chloride in methylbenzene with dry litmus |
blue |
blue |
| Test for the presence of water – anhydrous copper sulphate |
white |
blue |
| Reaction of copper with concentrated nitric acid |
blue solution and brown fumes |
|
| Reaction of copper (II) salts with sodium hydroxide (test for Cu2+) |
blue solution and colourless solution |
light blue precipitate |
| Reaction of iron(II) salts with sodium hydroxide – test for Fe2+ |
green solution |
green precipitate |
| Reaction of iron(III) salts with sodium hydroxide – test for Fe3+ |
orange brown solution |
red brown precipitate |
| Sodium chloride + nitric acid + silver nitrate – test for Cl- |
colourless solution |
white precipitate |
| Sodium bromide + nitric acid + silver nitrate – test for Br- |
colourless solution |
pale cream precipitate |
| Sodium iodide + nitric acid + silver nitrate – test for I- |
colourless solution |
yellow precipitate |
| Sulphate compounds and barium chloride |
colourless solution |
white precipitate |
| Heating copper carbonate |
green solid |
black solid |
| Zinc or magnesium in copper sulphate solution |
grey metal in blue solution |
colourless solution and black solid |
| Magnesium burning forming magnesium oxide |
silvery shiny solid |
white solid |
| Colours of groups 1 and 2 compounds |
white solids |
colourless if dissolved in water |
| Hydrochloric acid and ammonia - neutralization |
two colourless gases |
white solid |
| Chlorine water and sodium bromide solution |
two colourless solutions |
yellow solution |
| Chlorine water and sodium iodide solution |
two colourless solutions |
brown solution |
| Bromine water and sodium iodide solution |
two colourless solutions |
brown solution |
| Heating hydrated copper sulphate |
blue solid |
white solid |